Ask for 4ft doors for everything

Ask for power outlets above your lockers

Ask for more storage than you need

Ask for storage that is as generic and repositionable as possible. Once you're in your space you'll find better ways to organize/store

Ask for industrial-level uniform racks that won't pull out of the wall

Ask for a short throw projector, so the majority of the band hall is usable for color guard tosses

Ask for a larger ice machine (if you currently have one)

Ask for larger restrooms to accommodate kids changing clothes for rehearsals